
.app{
  width:100%;
  height:100%;
  display: flex;
  flex-direction: column;
}
header{
  width:100%;
  height:40px;
  background: #ccc;
  text-align: center;
}

.content{
  width:100%;
  display: flex;
  flex-direction: column;
  flex:1;
  overflow:auto;
}
.content::after{
  content:"";
  display:block;
clear: both;

}
footer{
  width:100%;
  height:40px;
  text-align: center;
  background: #eee;
}
  .list{
    height:100%;
    width:100%;
    display: flex;
    justify-content: space-between;
  }
  .list li {
    height:100%;
    width:80px;
    list-style: none;
    display: flex;
    justify-content: center;
    align-items: center;
    background: fuchsia;
    border-radius: 5px;
  }